Lately, a wireless broadband (WiBro) mobile internet business begins in earnest. Accordingly, the introduction of WiBro/WiMAX systems has been actively promoted in various domestic companies.
In order to hold a dominant position on technology negotiation and exporting against foreign equipment, the WiBro/WiMAX system must have a specialized functional module that provides distinguishable features and advantages.
Conventionally, a fixed bandwidth was allocated to transmit and receive information. Therefore, it was impossible to dynamically change a bandwidth according to a channel state around a system.
If communication quality deteriorates or communication was interrupted due to interference of peripheral channels, it was required to replace a filter after disassembling a device or a device is replaced with another device which was designed to operate in a different bandwidth because it was impossible to change a bandwidth instantly. That is, such a replacement operation was annoying and time consumption operation. Furthermore, the replacement process became a factor that deteriorates the service quality and increases the dissatisfaction of customers because the replacement process interrupts communication for a comparative long time.